Apparatus for coating pipe



May 24, 1949- R; c. STROMQUIST APPARATUS FOR COATING PIPE 2 Sheets-Sheet1 ATTORNEYS Filed Oct. 25, 1945 y 1949. R. c. STROMQUIST APPARATUS FORCOATING PIPE Filed Oct. 25, 1945 2 Sheets-Sheet 2 ATTORN EYS v my .QN N,QM. W l I I HHH Hn h .FHHHQ a I! r 3 k Q w \\\\\\\\\\N\\\ 1. iniw 3 3m N:u nnwnnnw Hun- R 9 3 Q Patented May 24, 1949 UNITE s'rrss Mrs- T OFFlCEAPPARATUS FOR COATING PIPE Russell 0. Stromquist, Westfield, N. J.,asslgnor, by mesne assignments, to Koppers Company, linc., a corporationof Delaware Application October 25, 1945, Serial No. 624,459

bitumen hardens well above atmospheric temperatures, it is applied hotand in liquid condition. As hot, liquid bitumen will not adhere to coldmetal surfaces, two methods have'been employed to effect adhesion: (1) apriming coat'is first applied and dried, or (2) the entire pipe isheated before the coating is applied. Both of these are time-consumingand expensive.

According to a method which I have invented, and which forms thesubjectof my copending application', Serial No. 624,458, filed October 25,1948, I subject the surface to be coated to an intense heat immediatelyprior to or simultaneously with the application of the hot liquidbitumen. In this way the skin of the pipe to be coated is heatedmomentarily to a temperature high enough to ensure the necessary bondbetween the metal and the bitumen without, however, appreciably raisingthe temperature of the whole pipe. I thus avoid the need for applying apriming coat or preheating the entire pipe.

the heating and coating unit through it, the heater preceding thebitumen so that the skin of the pipe is heated to a temperature at whichthe bitumen will adhere just before the hot, liquid bitumen is applied.In order to increase the efiectiveness of the heat and the speed withwhich the temperature of the pipe skin is raised, the heater is confinedbetween two circular bafiies which travel with it.

In the accompanying drawings, I have illustrated a preferred embodimentof the coating apparatus of my invention, although others embodying thesame principles could doubtless be devised. In these drawings,

9 Claims. (Cl. 9113) action of fluids passing through them. As theFigure 1 is a side elevation of the entire apparatus showing the pipe tobe coated, mounted for rotation at the left hand end of the apparatus.with the flame head and bitumen nozzle retracted and their connectionsto the various sources of supply shown,

Figure 2 is a transverse section taken along line 2-2 of Figure 1,

Figure 3 is a transverse section taken along line 3-3 of Figure 1,

Figure 4 is a VerticaLlongitudinal section, on

an enlarged scale through a pipe to be coated, showing in elevation thebitumen nozzle, the fiame head and their connections supported withinthe pipe, e

Figure 5 is a horizontal, longitudinal section through the pipe showingthe parts shown in Figure 4 in plan, and

Figure 6 is a vertical transverse section taken along line 6-6 of Figure4.

The apparatus shown in these drawings is supported on a long trestle I,comprising a pair of channel irons 2 supported on uprights 3 and tiedtogether by cross pieces 4. A pair of rails 5 mounted on the channelirons 2 form a track on which a carriage 6 is mounted and driven ineither direction by means of a motor I through driving connections 8comprising clutch, chains and sprockets. On this carriage are mounted anof the movable parts of the apparatus which I shall describe presently.

Mounted upon upright frames 9 at the left- I hand end of the trestle aretwo pairs of rollers I0 journaled in-bearing plates II and rotatablysupporting the pipe [2 to be coated. One or more of these-rollers isconnected to a power drive, n t

shown. For example the shaft 50 of one of the rollers i0 is providedwith a spur pinion 5| which meshes with a 'drive gear of any suitablepower drive.

Mounted on the carriage B is a supply kettle l3 containing the hotliquid bitumen which is kept in molten condition by means of the usualoil burner l4 supplied from a tank 15 likewise mounted on the carriage.The bitumen is heated to the application temperature in larger kettles,not shown, which are located alongside the apparatus, and transferred tothe smaller supply kettle l3,

-as needed. Mountedon the carriage in front of the kettle is a pump l6.driven by a motor l'l.

Outlets of which point toward the lower, inner face of the pipe and areclosely adjacent to it, as shown in Figure 4. A mixture of oxygen andacetylene is fed to this flame head by a duct 33 from a mixing chamber34 to which the gases are fed through flexible tubes 35 and 36 leadingfrom oxygen and acetylene cylinders 37 and 38 respectively. The flamehead32 is confined between two circular bailles 39 and 40 whichsubstantially fill thepipe and provide an enclosed space for the flamehead to operate in. The bitumen conduits 22 and 26 pass through thesebaffles and are secured thereto while a slot 4'! in baffle 39 providesfor the passage of the oxyacetylene duct 33. Auxiliary compressed airfor combustion is delivered to the space between the baffles 39 and 40through a duct 42 surrounding and concentric with duct 33, which ductlikewise passes through slot 4 i. This duct 42 is connected to a sourceof compressed air, not shown, through flexible hose 43.

The bitumen conduits, nozzle and valve, an the flame head andconnections are supported by means of rollers 44 journaled between pairsof plates 45, the flame head lying between the nozzle and the supportingrollers. As in the case of the bafiies 39 and 40 the bitumen conduitspass through and are secured to these plates -45 while the oxyacetyleneduct 33 and the auxiliary air duct 42 passthrough slots 46 therein.During the coating operations, the bitumen nozzle and flame head andtheir various connections are supported by the rollers 4'4 upon the pipeitself. Supported upon the uncoated inner surface of the trestle inalignment with and closely approaching the inner end of the pipe I2 is achannel 4! which supports these parts when in their retracted or partlyretracted position. It will be understood that a, plurality of sets ofrollers 4-2 are provided so that ample support is provided at spacedintervals.

The apparatus operates as follows: The pipe to be coated is placedhorizontally upon the rollers 10, whereupon the carriage is moved to theleft (referring to Figure 1) until the valve 23 and the flame head havepassed through the pipe and project beyond it on the far side. The motor16 is started to circulate bitumen from the kettle through the piping,previously described, and back to the kettle, whereupon the flame isignited and the valve opened to permit the discharge of hot liquidbitumen through the orifice 25 of the nozzle 24. The pipe is thenrotated and the carriage moved to the right by means of motor i anddrive 8 so that the flame head, and immediately following it the streamof bitumen discharge from the nozzle orifice, move progressively alongthe length of the rotating pipe. When the flame-head and valve havepassed through the pipe to the position, shown in Figure 1, the movementof the carriage is arrested, the flame is shut off and the valve closed.Circulation of the bitumen continues after the closing of the valve sothat there is no danger of its freezing in the conduits between coatingoperations.

By using one 6" flame cleaning head it is pos-- sible to coat theinterior surfaces of pipes at a rate of approximately 1050 square feetper hour, with a consumption of oxygen and acetylene gases ofapproximately 137 cubic feet per hour for each gas. Auxiliary compressedair is supplied at the rate of approximately 900 cubic feet per hour. Ifit is desired to coat pipes at a rate greater than 1050 square feet perhour, additional flame cleaning heads may be added to this mechanism;thus the rate at which the pipe can be coated will be increased by thenumber of flame cleaning heads used and will be in a direct ratio to thequantity of oxygen and acetylene gases consumed per hour based on anapproximate coating rate of 1050 square feet per hour per 137 cubic feetof oxygen and 137 cubic feet of acetylene gases consumed per hour. Thediameter of the pipe and the rate at which the pipe is desired to becoated will govern the number of flame cleaning heads to be used.

The temperature to which the interior skin of the pipe must be heated inorder to effect a satisfactory bond between the metal and the bitumenwill vary dependin upon the nature of the bitumen used. The temperaturerequired to effect a bond between the conventional coatings used forlining pipe must be'somewhat in excess of 200 F. This temperatureapplies to a coal-tar coating conforming to A. W. W. A. (American WaterWorks Association) specifications 7A.5 1940 and TAG-1940 for coal tarprotective coat- 5 ings for steel water pipe.

The oxyacetylene flame is a high temperature flame which can develop alocal temperature of at least 2000 F. and so cleanse the surface of thepipe of scale and dirt. The rate of movement of 4,0 the flame-cleaninghead is such that the pipe is neither burned nor overheated, but is suchthat the surface temperature of the pipe will be some what in excess of200 F. when the molten bitumen is applied to the surface from thenozzle.

I claim:

1. Apparatus for coating a metal pipe with hot, liquid bitumen whichcomprises a heater for locally heating the skin of the pipe to atemperature at which the bitumen will adhere to the metal, a nozzle atone side of the heater for applying hot, liquid bitumen to the heatedareas of the pipe, a support for the heater and nozzle at the other sideof the heater, and means for moving the heater along the pipe with thebitumen-applying means immediately following.

2. Apparatus for coating a metal pipe with hot, liquid bitumen whichcomprises a flame head for locally heating the skin of the pipe to atemperature at which the bitumen will adhere to the metal, a duct forsupplying oxygen and fuel to the flame head, a nozzle for applying hotliquid bitumen to the pipe immediately behind the flame head, a conduitfor supplying bitumen to the nozzle, a support for the nozzle prises aflame head for locally heating the skin of the pipe to a temperature atwhich the bitumen will adhere to the metal, means for supplying oxygenand fuel to the flame head, a nozzle for applying hot liquid bitumen tothe pipe immediately behind the flame head, means for supplying bitumento the nozzle, means for rotating the pipe, means for supporting theflame head and nozzle upon the uncoated inner surface of the pipe andmeans for moving the flame head and nozzle through the pipe with theformer in advance of the latter.

4. Apparatus for coating the interior. of a metal pipe with hot, liquidbitumen which comprises a flame head for locally heating the skin of thepipe to a temperature at which the bitumen will adhere to the metal,means for supplying oxygen and fuel to the flame head, bafiles at eitherend of the flame head to confine and concentrate the heat, a nozzle forapplying hot, liquid bitumen to the pipe immediately behind'the flamehead but beyond the rear baflle, means for supplying bitumen to thenozzle, means for supporting the flame head and nozzle upon the uncoatedinner surface of the pipe, and means for moving the flame head andnozzle relative to the pipe with the former in advance of the latter.

5. Apparatus for coating a metal pipe with hot, liquid bitumen whichcomprises a flame head for locally heating the skin of the pipe to atemperature at which the bitumen will adhere to the metal, means forsupplying oxygen and fuel to the flame head, means for supplyingauxiliary air for combustion to the flame head, a nozzle for applyinghot, liquid bitumen to the pipe immediately behind the flame head, meansfor supplying bitumen to the nozzle, means for supporting the flame headand nozzle upon the uncoated surface of the pipe, and means for movingthe flame head and nozzle relative to the pipe with the former inadvance of the latter.

6; Apparatus for coating the interior of a metal pipe with hot, liquidbitumen which comprises a flame head for locally heating the skin of thepipe to a temperature at which the bitumen will adhere to the metal,means for supplying oxygen and fuel to the flame head, baflles at eitherend of the flame head to conflne and concentrate the head, means forsupplying auxiliary air for combustion to the space between the baffles,a nozzle for applying hot, liquid bitumen to the pipe immediately behindthe flame head but beyond the rear baflle, means for supplying bitumento the nozzle, means for rotating the pipe,

means for supporting the flame head and nozzle upon the uncoated innersurface of the pipe, and means for moving the flame head and nozzlerelative to the pipe with the former in advance of the latter.

7. Apparatus for coating a metal pipe with hot, liquid bitumen whichcomprises a flame head fof'locally heating the skin of the-pipe to atemperature at which the bitumen will adhere to the metal, means forsupplying oxygen and fuel to the flame head, a nozzle for applying hot,liquid bitumen to the pipe immediately behind the flame head, means forsupporting the flame head and nozzle upon the uncoated surface of thepipe a supply kettle for liquid bitumen, a pump for transferring liquidbitumen from the kettle to the nozzle, a carriage for the kettle, pump,flame head and nozzle and means for moving the carriage to move theflame head and nozzle relative to the pipe with the former in advance ofthe latter.

8. Apparatus for coating the interior of a metal pipe with hot, liquidbitumen which comprises a flame head for locally heating the skin of thepipe to a temperature at which the bitumen will adhere to the metal,means for supplying oxygen and fuel to the flame head, baffles at eitherend of the flame head to confine and concentrate the head, means forsupplying auxiliary air for combustion to the space between the baifies,a nozzle for applying hot, liquid bitumen to the pipe immediately behindthe flame head but beyond the rear baffle, means for supplying bitumento the nozzle, and means for rotating the pipe, means for supporting theflame head and nozzle upon the uncoated inner surface of the pipe, asupply kettle for liquid bitumen, a pump for transferring liquid bitumenfrom the kettle to the nozzle, a carriage for the kettle, pump, flamehead and nozzle and means for moving the carriage to move the flame headand nozzle relative to the pipe with the former in advance of thelatter.

9. Apparatus for cleaning the interior of a metal pipe and coating itwith hot, liquid bitumen which comprises a flame-cleaning head forlocally heating the skin of the pipe to remove scale and dirt andraising it to a temperature at which the bitumen will adhere to themetal, a duct for supplying oxygen and fuel to the flame head, baiilesat either end of the flame head to confine and concentrate the head, aduct for supplying auxiliary air for combustion to the space between thebaflies, a nozzle for applying hot, liquid bitumen to the pipeimmediately behind the flame head but beyond the rear baflie, a conduitfor supplying bitumen to the nozzle, rollers for rotating the pipe,rollers for supporting the flame head and nozzle upon the uncoated innersurface of the pipe, a supply kettle for liquid bitumen, a pump fortransferring liquid bitumen from the kettle to the nozzle, a carriagefor the kettle, pump, flame head and nozzle and means for moving thecarriage to move the flame head and nozzle relative to the pipe with theformer in advance of the latter.

RUSSELL C. S'I'ROMQUIST.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 856,996 Custer et al June 11,1907 1,737,446 Atha Nov. 26, 1929 2,133,015 Boylan et al Oct. 11, 19382,295,702 Wissler Sept. 15, 1942 FOREIGN PATENTS Number Country Date844,437 France April 24, 1939 Certificate of Correction Patent No.2,470,796. May 24, 1949.

RUSSELL C. STROMQUIST It is hereby certified that errors appear in theprinted specification of the above numbered patent requiring correctionas follows:

Column 3, line 45, strike out the words the uncoated inner surface ofand insert the same in line 44, same column, after upon;

and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the case in thePatent Ofiice.

Signed and sealed this 25th day of October, A. D. 1949.

THOMAS F. MURPHY,

Assistant Gommz'ssioner of Patents.

